Semiconductors and silicon-based substrates are well known devices widely used in the semiconductor and electronics industry for various applications and devices. As an example, solar cells, a type of semiconductor type device, are well known devices for converting solar radiation to electrical energy. They can be fabricated on a semiconductor wafer using semiconductor processing technology. A photovoltaic cell or a solar cell includes P-type and N-type diffusion regions. Solar radiation impinging on the solar cell creates electrons and holes that migrate to the diffusion regions, thereby creating voltage differentials between the diffusion regions. In a backside contact solar cell, both the diffusion regions and the metal contact fingers coupled to them are on the backside of the solar cell. The contact regions and contact fingers allow an external electrical circuit to be coupled to and be powered by the solar cell. One or more embodiments pertain to photovoltaic cells or solar cells and photovoltaic fabrication processes. Such processes can include processing silicon substrates in preparation for subsequent solar cell processes as described below.